Are the Fritz!Box WiFi antennas directional in any way?

 

I'm using a Fritz!Box 7590 as mesh master, and a 7530 as a mesh unit. The 7530 is hanging on the wall about 30 cm off the ceiling. Problem is - the rooms behind that wall, still have very poor WiFi signal strength. It's a usual 1980's house, nothing strange about the walls. I'm thinking if the fritz is directional, I'm effectively pointing it the wrong way?